Anyone on the list who can offer an explanation about the following scenario? We have taken this up with providers at either end but it will take awhile to filter up to the ASes in question. We were seeing a London to Singapore connection go via San Jose causing a 50%+ increase in latency. It appears that SingTel (AS7473) is only announcing ConnectPlus (AS9911) routes to Level3 (AS3356) in SJC. However they have many adjacencies in many countries and other routes of both AS7473 and it's other downstreams don't appear to be affected (although I haven't tested them all). Traceroutes are appended at the end but to see for yourself use 202.176.222.0 as a BGP or traceroute query in the Level3 looking glass for both London and any other location, then compare with 167.172.93.0 Checking another large AS at random, they see AS7473 announcing AS9911 routes in London. thanks Marty Show Level 3 (London, England) Traceroute to 202.176.222.212 1 ae-34-52.ebr2.London1.Level3.net (4.69.139.97) 0 msec 0 msec 0 msec 2 ae-42-42.ebr1.NewYork1.Level3.net (4.69.137.70) 68 msec 68 msec ae-41-41.ebr1.NewYork1.Level3.net (4.69.137.66) 72 msec 3 ae-71-71.csw2.NewYork1.Level3.net (4.69.134.70) 68 msec ae-81-81.csw3.NewYork1.Level3.net (4.69.134.74) 72 msec ae-61-61.csw1.NewYork1.Level3.net (4.69.134.66) 76 msec 4 ae-82-82.ebr2.NewYork1.Level3.net (4.69.148.41) 80 msec ae-92-92.ebr2.NewYork1.Level3.net (4.69.148.45) 84 msec ae-72-72.ebr2.NewYork1.Level3.net (4.69.148.37) 80 msec 5 ae-2-2.ebr4.SanJose1.Level3.net (4.69.135.185) 144 msec 144 msec 144 msec 6 ae-74-74.csw2.SanJose1.Level3.net (4.69.134.246) 140 msec ae-94-94.csw4.SanJose1.Level3.net (4.69.134.254) 148 msec ae-64-64.csw1.SanJose1.Level3.net (4.69.134.242) 144 msec 7 ae-12-69.car2.SanJose1.Level3.net (4.68.18.4) 140 msec ae-32-89.car2.SanJose1.Level3.net (4.68.18.132) 140 msec ae-22-79.car2.SanJose1.Level3.net (4.68.18.68) 140 msec 8 SINGAPORE-T.car2.SanJose1.Level3.net (4.79.42.230) 140 msec 140 msec 136 msec 9 POS3-2.sngtp-ar2.ix.singtel.com (203.208.182.205) [AS7473 {APNIC-AS-2-BLOCK}] 148 msec 152 msec 203.208.182.105 [AS7473 {APNIC-AS-2-BLOCK}] 136 msec 10 ge-4-0-0-0.plapx-cr2.ix.singtel.com (203.208.183.173) [AS7473 {APNIC-AS-2-BLOCK}] 148 msec xe-1-0-0-0.plapx-cr3.ix.singtel.com (203.208.183.170) [AS7473 {APNIC-AS-2-BLOCK}] 140 msec 140 msec 11 ge-2-1-0-0.sngtp-dr1.ix.singtel.com (203.208.183.62) [AS7473 {APNIC-AS-2-BLOCK}] 348 msec so-2-0-0-0.sngtp-cr1.ix.singtel.com (203.208.149.181) [AS7473 {APNIC-AS-2-BLOCK}] 336 msec ge-3-0-0-0.sngtp-dr1.ix.singtel.com (203.208.183.66) [AS7473 {APNIC-AS-2-BLOCK}] 360 msec 12 ae0-0.sngtp-cr1.ix.singtel.com (203.208.183.57) [AS7473 {APNIC-AS-2-BLOCK}] 328 msec ge-4-0-0-0.sngtp-cr2.ix.singtel.com (203.208.182.102) [AS7473 {APNIC-AS-2-BLOCK}] 336 msec 202.160.250.226 [AS7473 {APNIC-AS-2-BLOCK}] 336 msec 13 ge-3-0-0-0.sngtp-dr1.ix.singtel.com (203.208.183.66) [AS7473 {APNIC-AS-2-BLOCK}] 348 msec 524 msec 416 msec 14 202.160.250.226 [AS7473 {APNIC-AS-2-BLOCK}] 328 msec 344 msec 203.208.232.234 [AS9911 {APNIC-AS-3-BLOCK}] 336 msec 15 203.208.129.29 [AS9911 {APNIC-AS-3-BLOCK}] 308 msec * 412 msec 16 203.208.232.234 [AS9911 {APNIC-AS-3-BLOCK}] 376 msec * * 17 * * * Show Level 3 (London, England) Traceroute to 167.172.93.1 1 SINGAPORE-T.car1.London1.Level3.net (212.187.160.190) 0 msec 4 msec 0 msec 2 so-0-2-0-0.sngtp-ar6.ix.singtel.com (203.208.151.133) [AS7473 {APNIC-AS-2-BLOCK}] 284 msec 276 msec 276 msec 3 203.208.152.134 [AS7473 {APNIC-AS-2-BLOCK}] 288 msec 284 msec 288 msec 4 ge-5-0-8-0.hkgcw-cr3.ix.singtel.com (203.208.152.37) [AS7473 {APNIC-AS-2-BLOCK}] 276 msec 276 msec ge-5-0-2-0.hkgcw-cr3.ix.singtel.com (203.208.152.117) [AS7473 {APNIC-AS-2-BLOCK}] 284 msec 5 * * * Router: mpr1.lhr1.uk.above.net Command: traceroute 202.176.222.212 traceroute to 202.176.222.212 (202.176.222.212), 30 hops max, 40 byte packets 1 195.66.225.10 (195.66.225.10) 0.991 ms 2.433 ms 0.927 ms 2 so-0-2-0-0.sngtp-ar6.ix.singtel.com (203.208.151.133) 455.799 ms 271.095 ms 254.167 ms 3 203.208.149.210 (203.208.149.210) 255.751 ms 254.794 ms 254.838 ms 4 202.160.250.226 (202.160.250.226) 263.850 ms 263.912 ms 292.504 ms 5 203.208.129.29 (203.208.129.29) 275.109 ms 282.247 ms 313.901 ms 6 203.208.232.234 (203.208.232.234) 265.677 ms 265.604 ms 266.072 ms 7 * * *